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Is this 12V battery better than Battle Born?

Batteries installed. Arrived both at 13.08 volts (30-40% SOC). Charged at 100A combined (50 each - per recommendation) in a couple of hours. Was pretty fascinating to watch it charge at 100A and then as it got over 90%, the voltage spiked up to the 14.6 set point and amperage dropped down. Floating at 13.6. I took a bunch of video, including taking the top off of one of them. At some point I'll fully disassemble. Load testing to come. In the meantime, these are the cells:


which, based on the part number inside that document, appear to be these cells: https://www.alibaba.com/product-detail/Lithium-Ion-Lifepo4-100ah-Battery-3_62457146993.html
 
I bought the 200ah version. Waiting for it to ship. I think it will be a good battery for the price. Putting it in my Host camper with a xantrex freedom sw 2012 2000 watt inverter charger. Pretty excited to try it out. Did Sok update the website when yours shipped? Mine still shows as processing.
 
I purchased from Amazon. The shipping information from Amazon and UPS didn't update as I would have expected along the way ... (too long to describe here) I was starting to get worried but then everything updated and the two batteries showed up the following day.
 
Progress! I've done almost all my testing... and I've been compiling the video along the way ... Tomorrow is a load test (I already completed the capacity test) and then I'll put a bow on the video and upload to my YouTube channel. I hope to get this out there tomorrow (well, technically later today - so Wednesday evening US Eastern time). Don't ask - I'm not giving away any spoilers here ?
 
LoveyourRV (Ray) just did a video about the 100AH batt. His testing is not as “sophisticated” as Will’s. He did open the case and the inside seemed “clean”, except SOK uses 2 8AWG internal wires to the posts. Ray also loaded the batt to about 150A discharge since the manufacturer said it would take it. Did not shutdown, but, I wish we could have seen the temp of the 8AWG internal wires.

@Tony, maybe SOK uses the same pair of 8AWG internal wires. That would be a limiting factor for me, but, the Prismatics and BMS have bolted connections, so increasing Internal wire size is easy.
Here is another more technical reviewer by mjlorton from his bench of testing equipment with discharge data:


Results: it is up to spec and he is happy with it.
 
I wrote to the manufacturer about the minor issues I reported and gave them the video. They replied thanking me for the video and said they found and fixed the problem with the cells moving around inside the case. They've been very responsive and inquisitive so far. That's a good sign.
 
I should finally receive the 200ah battery today. Long lead time, 26 days, but the website showed 25 days, so I guess they were right. From what I have read and watched and think the wait will be worth it to get double the capacity for half the price. I will let you know how the battery is working after I incorporate it into my Truck Camper. The battery will be connected to 2 200amp solar panels with a victron 100/35 mppt controller and a xantech inverter charger.
 
Will has a $400 120A LFP so why review a $600 100Ah?
Nothing special about it and you already saw the innards.
Apparently he was not very impressed with this battery. Too bad, sounded good.
 
Its usually best that the manufacturer has no idea that someone is going to review their product.
 
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Love your RV posted a 1 month update on Sept 7. Showed 95 AH usuable, did more testing, opened it further, did some internal temp testing At 70A draw.
when he gets another 1000 subscribers, he will be giving away some stuff including this SOK battery.
 
Crossposting this I wrote in another thread:

Would not recommend that SOK.

1. Recommended Charge Current 20 A. Your solar array will produce more than 20A on a daily basis, unless you have a tiny < 300W system. By daily charging above 20A, you'll be degrading the battery (or destroying the BMS. Not sure which of the two is the limitation for the 20A here).
2. BMS Discharge Cut-off Voltage >8.0 V. That's way, way too low for LiFEPO4 chemistry. You don't want to go lower than 10.50V (2.50V per cell). If you don't have your own external battery disconnect, then you've just bricked your battery.
3. BMS Discharge Cut-off Current 320A~340A. And finally... lol wtf? That's 70% higher than the peak current (200A). If you sized the wires in your system for 200A (or god forbid for the 100A continous rating), you'll soon have a burned wires/system, or burned down house. :eek:

As an aside:
4. BMS Low Temperature Cut-off 23°F. Why even bother have a low temp cutoff in the BMS if it's over 32F (0C?). You should never charge LiFEPO4 lower than 32F (0C), or else you will brick it. While you can technically discharge a LiFEPO4 below 0C, it's not recommended.
Discharge Temperature -22°F ~ 140°F
Charge Temperature 32°F ~ 140°F

So assuming you have that 23F BMS cutoff, it's "too high" to allow for the lowest discharge temp (-22F), and too low for the lowest charge temp (32F). It's the worst of both worlds, exactly what is it trying to satisfy?

Read the spec sheet carefully and decide if these limitations are acceptable you. Are you really OK with funding these Chinese companies for a race to the bottom?

So to answer the question, "Is this 12V battery better than Battle Born?" : my answer hell no.
 
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1) There are now discrepancies in the recommended charge rate. I see 0.5c (50 amps) https://www.sokbattery.com/100ah-12v-lifepo4-deep-cycle-battery.html but I also see 20 amps both there and https://www.sokbattery.com/media/sparsh/product_attachment/SK12V100.pdf
2) Yes, LVDC is too low and I asked about this and he seems fine with it being 2.0VPC. I'm pretty sure he'd listen to us and modify the BMS to cut off at 2.5 VPC (he already fixed the issue with the case I previously mentioned)
3) I don't know what happens at 200 or 320, but I did pull 100 sustained (with bursts to 125) and it barely got warm. It's properly sized for that.
4) Agreed, I don't know why this is so low; again I'm sure they'd be willing to modify

It's quite possible their philosophy is that the BMS is a *last resort* protection device and that connected equipment (e.g. Inverter) should disconnect at the recommended voltage (11v) and the battery should be fused. Although that doesn't explain their temperature cutoff.
 
Would not recommend that SOK.

1. Recommended Charge Current 20 A. Your solar array will produce more than 20A on a daily basis, unless you have a tiny < 300W system. By daily charging above 20A, you'll be degrading the battery (or destroying the BMS. Not sure which of the two is the limitation for the 20A here).
This is probably not as bad as it sounds. "recommended charge current" is not the same thing as "max continuous charge current. Most cell manufacture datasheets I've seen use 0.2C, 0.3C, or 0.5C for this value. For a 100Ah battery that would be 20, 30, or 50 and is just a recommendation. I don't know what the 'max continuous charge current' for the SOK battery is.

2. BMS Discharge Cut-off Voltage >8.0 V. That's way, way too low for LiFEPO4 chemistry. You don't want to go lower than 10.50V (2.50V per cell). If you don't have your own external battery disconnect, then you've just bricked your battery.
This is unreasonably low for a lifepo4 BMS in this day and age

3. BMS Discharge Cut-off Current 320A~340A. And finally... lol wtf? That's 70% higher than the peak current (200A). If you sized the wires in your system for 200A (or god forbid for the 100A continuous rating), you'll soon have a burned wires/system, or burned down house. :eek:
Not sure what's up with the discharge current cutoff, maybe its meant to accommodate short startup surges, maybe its meant as BMS protection, not battery current limiting solution, maybe its just improperly designed. But setting that aside, to the second part of your point, in my opinion it is not the BMS that should be protecting the wire, the wire should have an overcurrent protection device (fuse or breaker) close to battery positive, and should be protected regardless of what occurs with the BMS. At least this is what I would do.
 
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